Development of 4-degrees of freedom force feedback device with pneumatic artificial muscles and magnetorheological clutches

In this study, we developed a 4-degrees of freedom (DOF) force feedback device independent of its operational component comprising pneumatic artificial muscles and magnetorheological clutches. Research and development of force feedback devices is becoming popular in fields such as entertainment, remote operation, and rehabilitation. These areas of research are related to virtual reality and augmented reality. People are focusing their research efforts on force feedback devices that display three-dimensional virtual objects or can provide realistic force sensing as that of stroking the surface of a virtual object. Many of these devices comprise motors; hence, they are likely to be hazardous in the event of delayed response to an unexpected external force. In addition, their back drivability decreases when the motor output is increased via reduction gears. To solve these problems, we previously developed a 3-DOF force feedback device using pneumatic artificial muscles, which are structurally flexible and have a wide range of stiffness, and magnetorheological clutches. As the next step toward developing a 6-DOF device, we have developed a 4-DOF feedback device.